MEMS-Based Pyroelectric Thermal Energy Scavenger

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Technology Marketing SummaryA new type of microelectromechanical system (MEMS ) high efficiency heat energy converter, or scavenger, was invented by ORNL researchers. This device is based on temperature cycled cantilevered pyroelectric capacitors. The scavenger converts thermal waste heat to electricity that can be used to monitor sensor systems, or recycled to provide electrical power while simultaneously reducing thermal cooling requirements. Given the current state of global industry, which discharges over 100 terajoules annually of low-grade waste heat, this technology could save industrial sectors tens of millions of dollars while also reducing greenhouse gas emissions.DescriptionIn contrast to previous attempts to use temperature cycled pyroelectric materials as thermal energy harvesters, this invention can generate high rates of temperature change during the energy generation cycle with minimal power loss, leading to very efficient power generation. The device uses the heat source to thermally activate a bimorph structure and power temperature cycling through the converter. The overall energy conversion efficiency values are calculated to be several times larger than those achievable with any other competing thermal-to-electrical scavenging techniques.

The thermal energy conversion devices of this invention can be arranged into arrays sized for the heat source. The fabrication of these arrays can even be scaled to meet the needs of high volume, low cost manufacturing.Benefits

Potentially several times more efficient than other techniques for thermal to electrical energy conversion

Operates at higher frequencies, leading to higher peak and average power generation